#include<iostream>
#include<vector>
#include<queue>
#include<cstring>
#include<cmath>
#include<map>
#include<set>
#include<cstdio>
#include<algorithm>
#define debug(a) cout<<#a<<"="<<a<<endl;
using namespace std;
const int maxn=200;
typedef long long LL;
inline LL read(){LL x=0,f=1;char ch=getchar();	while (!isdigit(ch)){if (ch=='-') f=-1;ch=getchar();}while (isdigit(ch)){x=x*10+ch-48;ch=getchar();}
return x*f;}
LL a[maxn];
map<LL,LL>map1;
int main(void)
{
  cin.tie(0);std::ios::sync_with_stdio(false);
  LL t;cin>>t;
  while(t--){
    LL n;cin>>n;
    map1.clear();
    for(LL i=1;i<=n;i++) cin>>a[i],map1[a[i]]++;

    for(LL i=0;i<=100;i++){
        if(map1.count(i)){
            cout<<i<<" ";
            map1[i]--;
        }
    }
    for(LL i=0;i<=100;i++){
        for(LL j=1;j<=map1[i];j++){
            cout<<i<<" ";
        }
    }
    cout<<"\n";
  }
return 0;
}
